MLZ User Meeting & German Neutron Scattering Conference 2020

Inward shift in the spin wave dispersion of a stripe discommensurated Pr-based 214-nickelate

8 Dec 2020, 15:00

25m

Online event

Talk UM: Quantum Phenomena MLZ Users 2020 - Quantum Phenomena

Speaker

Avishek Maity

Description

Magnetic excitations in the spin-stripe phases of La-based 214-nickelates have been vigorously explored using INS for almost last three decades and still have remained an exciting research field, especially to understand their differences yet of their structural similarities with high-T${}_c$ 214-cuprates. In view of the reported two-dimensional antiferromagnetic nature, out-of-plane magnetic excitations are generally not expected in 214-nickelates. From the INS measurements of magnetic excitations in a stripe discommensurated Pr${}_{3/2}$Sr${}_{1/2}$NiO${}_4$ with magnetic incommensurability $ϵ=$ 0.4, here we present very compelling evidence for a sizable out-of-plane interaction ($\sim$2.2 meV) which was crucial to explain the observed shift of the spin wave dispersions towards the magnetic zone centers.

Reference: A. Maity, R. Dutta, and W. Paulus, Phys. Rev. Lett. 124, 147202 (2020).